Radiotelegraphy



L. F. FULLER.

RADIUTELEG'BAPHY. APPLICATION FiLED JUNE 18. 1917.

v Patented Ja l. 18,1921.

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- IHVENTOR L. Ff FULLER mil ion es e a l u LEQNLZLRD F. FUTEQLER, OF SAN FRANCISCG, CALIJEGRNIA. ASSIGNQR, MJESNE .tti'iSIGNMENTS, 'iLO THE UNITED STATES U ihi dffll tlwlt.

EAIJIOTELEG-RAPHY.

To alien/m it may concern lie it known that I, LEONARD F. FULLER, a citizen oi the United citates, and a resident of the city and county of San Francisco and State of California, have invented certain new and useful improvements in Radio- ;telee raphy, of which the following is a specification.

The invention relates to means of signaling and particularly to means for signaling with radio transmitters.

An object of the invention is to provide means for signaling involving interrupting and reestahlishing the arc.- 1

Another object of the invention is to provide unitary means for successively estab lishing and interrupting the arc.

The invention possesses other advantr geous features, some of which, with the foregoing, will be set forth at length in the following description, where I shell out ii'nc in full that form of the invention which i have selected for illustration in the drawings accompanying and forming part of the present specification. lit is to be understood, however, that the invention as expressed in. the claims is not limited to the specific embodiments shown in the drawings Referring to said drawings:

Figure .l is a diagramnmtic representation of one form of the system which is particularly applicable for low powered stations.

Fig. 2 is a iliagramn'iatic representation of a modification of a portion of the system to adapt it to high powered stations.

Fig. 3 i's a diagrammatic representation of another modification.

My present invention provides a means of signaling which contemplates opening and (dosing the antenna circuit. Opening the antenna circuit extinguishcs the arc and means are provided for reignitin the are as the antenna circuit is closed.

in t'KZUlSmiSSlOTI system coinprisegl an arc (recreation generator :2 which is grounded on one side, preferably the negative and connected on the other sidc to the antenna ti'irougrh the variable antenna inductance 2. Direct current is supplied to the are ieretor, by the generator 5, and a choke coill t? arranged in the load 7 connected to the antenna side of the arc. The are is suhiected to e strong transverse magnetic specification of Letters Patent. jPge-tmmntrgfli Jan 11% igg e;

Application filed June is, 1917'.

Eierial Tito.

field produced by the magnet coils 8 arranged in the lead '2'.

Arranged between the are and the antenna are contacts 9 and 11, the contact 11 being mounted on e lever 12, so that it is readily movable to open and close the antenna circuit. The lever is norms-ii held in position to open the circuit by e spring 13. The lever may be directly connected to a sending key or it may be operated by other suitable means, such as the solenoid 1% arranged in a local circuit with at key to and battery It. i Vhen the key is closed, the antenna circuit is closed and when the key is opened, the spring 13 opens the on terms circuit.

The potential of the genial-otter 5 and the inductive kick of the inductance of the magnetizing windings is usually not suf hcicnt to reignite the are, after the antenna circuit has been opened and supplementary means are provided for reigniting the arc.

Connected across the are is a spark circuit containing the spark gap 17, the secondary ot thetransi'ormer 1.8 and the npacity l9, shljuiting the secondary. it. stopping resistance 721 is arranged between the spark gap which sets up radio i rcouencv surges which ignite the main arc.

in this arraiurement, the current in the magnetizing windings varies. and while this feature is deleterious in large stations on. account of the large inductance of the mag nctiziug windiiujs, it does not seriously intcri'crc with the operation of smell stations.

in ordcrto maintaii'i the current in the magnetizing winding constant, as the arc is cxtin nlished and ignited, a separate generator 2-1- is arranged in shunt "with the mag} netizing winding; as shown in his; This generator is chosen so that its E. M. h. equals the product of the resistance of the winding h the normal. current flowing; therethrough when the are is burning. hen the arc is burning, the field is excited by current from the generator 5 and when the arc is extinguished, the field is excited by cur- 3 rent from the generator 24-.

In Fig. 3 I have shown a separately excited magnetic field, the magnetizing winding 8 in this instance being in series with the generator 25 and independent of the arc circuit. The constructions and 3 are particularly adapted for high powered systems in which the inductance of the magnet win-dings is great, but in systems of small power, the apparatus shown in Fig. 1 may he advantageously employed.

E claim:

1. An are system for radio signaling, comprising an arc, a current supply and antenna circuit connected to the are, means for opening and closing the antenna circuit and means operative simultaneously with the closing of the antenna circuit for igniting the arc.

2. An are system for radio signaling com prising two normally stationary electrodes, between which an arc is formed, a current supply connected to the are, a normally open antenna circuit connected to the arc, and means operative in time with the closing of the antenna circuit for igniting the arc.

3. An are system for radio signaling comprising two normally stationary electrodes between which an arc is formed, a current supply connected to the are, a normally open antenna circuit connected to the arc, and means operative in time with the closing of the antenna circuit for producing an ignition spark across the arc.

shown in Figs. 2'

- 4. An are system for radio signaling co1nprising an are, a current. supply connected to the arc, a normally open antenna circuit connected to the are, a spark circuit shunted around the arc and adapted to produce an ignition spark across the arc as the antenna circuit is closed and antenna circuit.

5. An arc system for radio signaling comprising an arc, a current supply connected to the arc, an antenna circuit conncitcd to the arc, a switch in the antenna circuit. a spark circuit shunted across the arc. a switch controlling said spark circuit and means connecting said switches whereby they are ciosed substantially sin'niitaneously.

(3. An are system for radio signaling comprising an arc, a current supply conncctedto the are, a magnet winding for producing a transverse field on said arc, a current supply connected across the magnet winding, an antenna circuit connected to said arc. means for opening and closing the antenna circuit and means operative simultaneously with the closing of the circuit for, igniting the are.

7. An arc system for radio signaling comprising an arc, a current supply and antenna circuit'connected to the arc, means for opening and closing the antenna circuit, the said means when opening the circuit serving to extinguish the ar: and means for rcigniting the arc.

In testimony whereof, I have hereunto set my hand at an Francisco, California, this 6th day of June, 1917.

LEONARD F. F ULLEH.

In presence of- H. G. PROST.

means for closing the i 

